Improved furniture-caster



J. H. BLUOMIIELD. FURNITURE CASTBR;

No, 36,890. Patented Nw 11, 1862.

` MEW/ware@ l UTED STAT-Es PATENT OFFICE lJ. HABLOOMFIELD, or- CHICAGO, ILLINoIs.

sMPRoi/,ED Fu'aNlTuRs-cA-STER;

To aZZ whom. ity may concern.: I

Be it' known that I, J. H. BLooMFIELD, of the city of Chicago, in the county of Cook and- State of Illinois, have invented a 'new andusefnl Improvement in Furnture-Castersrand represents the ange orrim which retains the ball' B in place, unattached.

` Similar letters .,'ln the di'erent figures in` said drawings represent and denote the corresponding parts of myinvention.

To enable others skilled in the art to stand the construction of my improved caster, I will now proceed to describe'the same with particularty.

The materialA of which I construct my improved caster is generally cast-iron; but itmay be made of brass or any other suitable metal. The ballmarked B, I prefer-to make of castiron in all cases'. 4 l

The .nature oimy invention consists in constructing a caster in such a manner that a ball may be and is used in the place and stead of the common `wheel orrswivel forthat `part .of the caster-upon which the furniture is rolled or moved from one place to another, thecaste'r being at the same time' much stronger, more durable, and less liable to .get out of repair I than the ordinary kind.

In'the accompanying drawings, A represents a socket whereby the caster-may be attached to the legs or supports of the furniture. G is a cup or socket 'to 'contain' theballmarked B in the drawings; and D is a circularliange or rim y which, for the purpose o f retaining and keep` ing the ball B in place, is attachedandfastened to the-lower edge of the cup AC by means ofthe screw cut'in the outer circumference of the' liange and inner circumference of the cup C, as Vshownl in the drawings, or by any other equivalent and suitable z method. The internal diameter of the cup C, as may bevseen in4 the drawings, is greaterl thanthe diameter of under? the ball B, which is kept inthe center of the "cup by the points orsupports@ c, upon 'and within whichit freely Y moves. These sup'- ports are the only points of contact between the'ball and cup. The entire 'weight of the furniture,when at rest, falls on the point a,j and when in motion the whole of fthe friction caused by its weight is at the point'aand two ofthepoints c,.or only one. 'e 4 The point or support u in the apex of -tlie cup.` is a projection cast upon it, and nota separate' anti-friction piece inserted therein `.and the points c, (which treceive the lateral pressure of the ball,`),lying in the'same horizontal-plane, are arranged about the interior of the cup at equal distances from each other, so that a straight linedrawnfroxn one of said points to the, adjacent point will subtendan are' of exactly one/ hundred aud twenty degrecs. 'By-thevpeeuliar` arrangement of the three points c,'in` whatsoever direction the easterv may be movedthef1ateral pressure 'of the ball cannot come upon vmore than two points', and when." moved in either of three directions-namely, j of the lines passing throughv the center of the balland' either of the said three points-the lateral pressure of the ball can come upon, only one of lthe said points,I thus. occasioning the least possible amount of friction, which object. is effected 'only when the number of points is threeand Vwhen these three points are arranged lin precisely 'the manner described. The lower part of. the ball B projects below the lower edge of the flange D sufficiently to permit it torroll freely about on the door'. n

I do not claim the meth d of attaching the caster to the furniture by the socket A,nor lany particular method; but it may be attached in any suitable manner;.`but n What I claim as my invention isv i The peculiar arrangement ofthe th ree points c, in combination with the point a, when'thc structed, arranged, and operating Vsubstantially as and for the purposes delineated and set forth. 4 J. H. BLOOMFIELD.

Witnesses:

F. W. H. ROGERS,-

W. E. Mahrs.

same are used in" combination with-thc cup. and ball of a furniture-caster, all being con-- 

